Switch mechanism



July 22. 1924. 1,501,943 F. S. DENISON SWITCH MECHANISM Filed Aug. 7, .1922 2 Sheets-Sheet'l Patented July 22, 1924.

UNITED STATES PATENT OFFICE.

FREDERICK S. PENISON, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR TO MINNEAPOLIS HEAT REGULATOR CO., OF MINNEAPOLIS, MINNESOTA, A CORPORATION OF MINNE- SOTA.

swrrcn MECHANISM.

Application filed August 7, 1922. Serial No. 580,359.

mechanismis adapted for use as a circuit-- changing means and constitutes an improvement upon a switch mechanism disclosed in the prior pending application of the inventor hereof, Serial No. 427,851, filed December 2, 1920.. This mechanism is adapted for substantially the same uses as the switch mechanism disclosed in the prior application above mentioned. An example of a specific use of this invention is in temperature regu lating systems wherein the heat-generation of a furnace is thermostatically controlled by means of an electric circuit adapted to start or .stop the motor controlling parts of the heatproducing medium. In the embodiment of the invention here disclosed, a switch is auto- -matically operated by a secondary circuit of relatively low voltage. The switch controls the primary higher voltage or motor circuit. The switch medium is selectively operated 3o by electro-magnets to control the primary circuit. More specifically, an armature is selectively actuated upon energization of an electromagnet in a secondary circuit throu h a circuit-closer and this armature not only it also functions to interrupt the secondary circuit and to present another secondary circuit adapted to be closed by subsequent circuit-closer movement whereby the armature is oppositely moved to reverse the previous primary circuit condition. In this improved form the movable contacts of the primary switch and secondary switch are mounted upon a single instrumentality pivotally functions to change the primary circuit butborne by the frame for oscillation by the of the invention, but it is to be understood that the invention is not confined to the exact features shown, as various changes may be made within the scope of the claims which follow.

. In the drawings:

Figure 1 is a view in side elevation o the mechanism;

Figure 2 is a view in end elevation thereof;

Figure 3 is a fragmentary view in plan of the portion of the switch carrying the movable contacts; 1

Figure 4 is a partial vertical sectional view on the line 4.4 of Figure 3;

Figure 5 is a'detailed fragmentary view in side elevation of the connection between the armature and rock-shafts; and

Figure 6 is a wiring diagram.

In this selected embodiment of the invention the switch mechanism is preferably supported by a frame which comprises a pair of arched side plates 7 and 8 secured to each other in spaced relation. Each leg of each plate is provided with a short flange 9 adapted to rest upon or to be screwed to a bracket 11 carried by a panel frame 12.

Three sets of movable contacts are borne by the frame, one set to open and close a primary or relatively high voltage circuit and the other two sets are adapted singly to present'two secondary circuits'to a circuitclosing means, such' as a thermostat. Each of said sets has a movable contact and all movable contacts are mounted for simultaneous operation by means of a single armature movable in opposite directions in accordance with movements of the thermostat or other circuit-closing means. Electromagnets are opposedly carried by the frame and the armature depends therebetween so that upon energization of either electroma nets the armature is thereby moved and a contacts operated.

In the disclosed construction, the movable. contacts are all operated by a member fast on a shaft 14 journaled in alined apertures in the crown portions 15 and 16 of the opposed arched side plates 7 and 8. The shaft 14: has fixed thereto a hub 17 adapted plates-by means of the pin 24. Spacing blocks 25 are also mounted on the pin 24 on either side of the lever. The other arm 27 of this lever depends between two opposed electromagnets carried by the frame and functions as an armature. These electromagnets are angularly U-shaped and are formed of laminated metal as shown in Figure 2. The base, of each electromagnet is secured between adjacent legs of the. side plates and held therebetween by means of the screws 28. The polar arms 30 of the electromagnets project horizontally toward each other and are terminally spaced apart a distance sufficient to permit the desired amplitude of movement of the armature and close enough to obtain the desired strength ofmagnetic field set up by either magnet upon energization by an electric current.

received loosely within apertures in the'innerends of the spaced strips 53 integrally joined at their outer ends to form a. plate 54. The contact 55 is carried by the plate 54 and projects above the upper surface thereof. The inner end portion of the plate 54 is apertured to receive therein the end of a tension spring 56. The other end of this spring is hooked about the spacing rod 57 carried between the strips 47. Thus when the rock-shaftis turned from the full line position shown in Figure 4 to the dotted line position, the axis of tension of the spring passes through the axis of the pins 52, pivotally joining the pairs of spaced strips 47 and 53. This passage through the line of centers tends to cause the plate 54 to snap from the elevated position shown Coils 10 and 20 are mounted one upoin in full lines to its depressed dotted-line poeach of the lower arms of the electromagnets. Thesecoils are adapted to be selectively and singly energized so that the armature 5 is drawn toward the energized coil. Movement of the armature imparts torque to the hub and shaft 14 whereby the movable contacts are operated.

The fixed contacts are three in number and are conveniently carried by one of the side plates'to project outwardly from one side of the frame. A piece of strap iron is bent into angularly U-shaped form and its base 31 is held to the side plate 8 by means of the screw 32 so that the upper and lower legs project horizontally to provide an upper bracket 33 and a lower bracket 34.

Binding posts 35 and 36 are mounted upon the upper bracket 33 and downwardly project therethrough being insulated therefrom by the insulation 37. The lower end of the st 35 downwardly presents a contact 38 while the post 36 similarlypresents a contact 39. A binding post 41 is mounted upon the lower bracket 34 and up wardly projects therethrough being insulated therefrom by insulation 42. The upper end of this post 41 upwardly presents-a contact 43 in opposed spaced relation-to the contact 38 of the upper post 35. A detent to limit the throw of the member carrying the movable contacts is provided by the screw 44.

The three movable contacts are carried by a single member fast at one end to the sition, thus effecting a sharp, quick break. This plate contact 55 is, adapted to make and break with the contact 39 of the post 36.

The two other movable contacts are carried by a metallic flange 58 secured to, and insulated from one of the strips 53, preferably the outer. This is placed between insulation 59 and secured to the outer strip 53 by the screws 61 and 62. A backing plate 63 is preferably interposed between the screwheads and the adjacent insulation. The outer end of the finger is outwardly offset and flattened to present a disk 64 between the opposedfixed contacts 38 and 43.- This disk is. provided with contacts upon both faces, the contact 65 being upon the upper face while the contact 66 is upon the lower face.

A mode of employin mechanism may rea ily be explained by means of the wiring diagram Figure 6. The employment here suggested is in connection with a thermostat and thermostatic circuit whereby thermal changes may open and .close an electric circuit such, for example,

as to cause the starting and stopping of an electric motor.

this improved switch I The electric motor 67 is connected in series in a circuitwhich may be termed the primary circuit and which is provided by be opened and closed by means of the contact 55 when moved away from, or into env gagement with the fixed contact 38. In Fig ure 1, the primary circuit is shown as broken between the contacts 38 and 55, while in Figure 6 the primary circuit is shown as closed.

As above noted, the movable contacts are simultaneously moved by turning of the rock-shaft 14 upon -energization of one of the electromagnets to attract the armature 27. Electric energization of the electromagnets is efiected thermostatically. This mechanism is such that, upon energization of a selected electromagnet and movement of the armature thereto, the energizing circuit is immediately broken and another circuit presented through the other electromagnet to be closed upon subsequent movement of the thermo-bar.

' The thermostatic circuit is preferably operated by a lower voltage providedby a transformer 73 conveniently located upon. the panel frame 12. The main lines 71 and 72 are connected to the primary terminals thereof while the wires 74 and 75 lead from the secondary terminals thereof. The wires '74 and 75 are connected to posts 76 and 77 on the panel. The wire 78 connects the posts 76 to the screw 62 and therefore to both con-' tacts 65 and 66. Thus connection is had between one secondary terminal and the con-' tacts 65 and 66. The other secondary is connected by its wire 75 with the wire 79 of the thermostat bar 81 which is of any suitable type andisadapted" atures to effect electrical connection with either of the two contacts 82 and 83 of the two sides of the thermostatic circuit. The contact 82 is connected by the wire 84 to the panel post 85 and by the wire 86 to the electromagnetic coil 20. The other. end of this coil is connected by the wire 87 to the contact 43 and thus a secondary circuit may be closed by electrical engagement .of the movable contact 66 with the contact 43.

In the position of the'apparatus shown in Figure 6, it may be assumed that the motor is employed in connection with a heating plant which, as the motor is shown running,

has produced heat adjacent the thermo-bar 81 to cause it to bend to connect its wire 75 from one side of the secondary circuit with the hot side contact 83, whereupon the current traverses the wire 88 to the panel'post 89 "thence by the wire 91 to the coil 10, thence by the wire 92 to the contact to the contact 66, wire 78, post 76 and wire 74 to the transformer. The coil 10 is thus energized, the armature 27 drawn thereto and the contact 55 is thus moved from the contact 38 and the motor circuit thus opened while the contact 65 is likewise moved from the contact 66, thus opening the thermostatic circuit through the coil. The apparatusis at difierent temper-- and said rock's'haft, an oscillatable arm on said shaft parallel to said link, a primary circuit contact carried by said arm, contacts for secondary circuits carried by said arm and insulated both from the arm and the primary contact, fixed primary and secondary contacts carried by said frame in position to be contacted by said contacts on said oscillatable arm.

2. An electric switch mechanism, including a frame, a rock-shaft on the frame, an arm secured to and projecting from the shaft, opposed brackets projecting from one side of the frame, a primary circuit contact fixed to one bracket, and two secondary circuit contacts fixed each to a bracket in opposed relation, a member mounted to rock on said frame, a primary circuit contact on said member adapted'to make and break the primary circuit through said fixed primaryv contact, contacting means adapted alternately to engage the fixed secondary contacts to complete a circuit through one and simultaneously to break the circuit through the other, an armature movably mounted on said frame to rock said memberandthereby operate all said member contacts, and electromagnets on said frame and adapted upon selective energization to move the armature in different directions, whereby both the members are selectively rocked.

3. An electric switch mechanism including a frame, fixed primary and secondary circuit contacts on the frame, an arm mounted to rock on the frame, a fixed primary circuit contact on the frame, two fixed contacts for two secondary circuits on the frame in opposed spaced relation, a movable primary contact mounted on said arm and movable second circuit contacting means on said arm, both said contact and contacting means being insulated fromone arm and each other, whereby the contacts are adapted .upon rocking of said arm to change the three circuits, electromagnets, an armature movably mounted on the frame and adapted to rock said arm, electromagnets on the frameand adapted upon selective energization .to move the armature and thereby change the position of all said contacts.

4. An electric switch mechanism including a frame, electromagnets on the frame, an armature pivoted on the frame between the electromagnets to be selectively shifted in reverse directions thereby, a rock shaft on the frame, a connection between said armature and shaft to oscillate the shaft,'a pair of spaced arms insulatedly mounted on said shaft, a contact member pivotally mounted between said spaced arms, contacts on opposite sides of said contact member, spaced contacts on said frame opposite said contacts on said contact member, and a coiled spring arranged between said spaced arms and connecting the rear end of the latter with said contact member, said spring being constructed and arranged to hold said contact member into shifted position on oppo-.

site sides of the pivot connecting said contact-arm to said spaced arms.

In Witness whereof, I have hereunto set my hand this 4th day of August, 1922. v

4 FREDERICK S. DENISON. 

